Three pieces of paper in a single file
Four men wrote a letter in October 1941 that bypassed every level of the institutional hierarchy inside a classified government establishment. The letter went straight to Winston Churchill. File HW 1/155, held at The National Archives, is what survives of what happened next.
HW 1/155 contains three documents. The first is a letter dated October 21, 1941, headed “Secret and Confidential: Prime Minister Only, Hut 6 and Hut 8,” signed by four cryptanalysts of the Government Code and Cypher School (GC&CS): Alan Turing, Gordon Welchman, Hugh Alexander, and Stuart Milner-Barry. The second is a handwritten minute from Churchill to General Ismay, dated October 22, 1941, bearing a red “Action This Day” sticker, a specific administrative label Churchill used to signal that a matter required an immediate response. The third is a typed reply from Ismay to Churchill, dated November 18, 1941. The National Archives published an article drawing attention to the file on August 3, 2026.
The letter, read for what it says
The October 21 letter named three specific operational failures. First: the Hollerith section at Bletchley Park, run by a Mr. Freeborn (first name not established in the record), had stopped running night shifts for want of personnel, causing a delay of at least twelve hours every day in locating naval cipher keys. Second: Middle East wireless intercepts carrying “Light Blue” intelligence had sat undecoded since at least May 1941 for want of trained typists, a backlog of roughly five months. Third: a promise made in July 1941 to assign Women’s Royal Naval Service (WRNS) personnel to test results produced by the bombe machines had not been honored by October.
The four signatories stated that they were acting on their own initiative and without institutional sanction. The letter also praised Commander Travis, then responsible for Enigma decryption operations at GC&CS, by name for his role in supplying bombe machines, while making clear in the same breath that the staffing shortages were not his responsibility, a deliberate act of record-making about both what Travis had done and who was not to blame for what remained undone.
The requests, which were not large
The letter requested approximately 20 untrained Grade III women clerks for Hut 8, approximately 20 trained typists for Hut 6, and a WRNS detachment to take over bombe testing. It also raised a secondary concern: skilled male staff at both Bletchley Park and the British Tabulating Machine Company in Letchworth were liable to military conscription, which would remove further operational capacity.
Churchill had visited Bletchley Park on September 6, 1941, his only recorded personal visit, roughly six weeks before the letter was dispatched. The file draws no connection between that visit and the letter; the proximity is context, not document.
Writing past the institution
The four signatories held no authority to write to the Prime Minister, having passed over their entire management chain, an act they acknowledged within the letter. Their stated reason for bypassing the institutional chain was the chain’s prior failure: the July 1941 WRNS commitment, cited as a promise that had not been honored. Whether that justification was adequate is not something the record settles.
The letter was carried by hand to 10 Downing Street by Milner-Barry. According to his own account, published in 1986 in the journal Intelligence and National Security, he traveled to London by train, took a taxi to Downing Street, and handed the letter to Brigadier Harvie-Watt, Churchill’s Parliamentary Private Secretary, who accepted it and undertook to deliver it urgently. That account belongs to what Milner-Barry later recalled, not to the 1941 documents in the file.
The handwritten note and its label
Churchill’s minute to Ismay, dated October 22, 1941, directed that Bletchley Park’s requirements be treated as a matter of extreme priority and demanded written confirmation that action had been taken. The minute says nothing about the four signatories, nothing about how the letter reached Churchill, and nothing about the act of institutional bypass it represented. Whether Churchill noted or was indifferent to the route the letter had taken is not recorded.
November 18, 1941: the machinery moved
Ismay’s reply, dated November 18, 1941, reported that he had contacted the Ministry of Labour and the Admiralty department overseeing WRNS assignments, directing both to give Bletchley Park’s staffing requirements extreme priority. Brigadier Menzies, identified in the file as chief of MI6, had confirmed to Ismay that the supply of labor was being rapidly addressed. Ismay’s letter does not declare the matter closed; it states that the process was not yet fully complete as of its date.
The silence after November 18, 1941
File HW 1/155 contains no document recording when all staffing requirements were finally satisfied. Milner-Barry wrote in 1986 that almost from the point of Churchill’s intervention conditions at Bletchley Park began to improve: staff bottlenecks eased and the supply of bombe machines accelerated. That is his retrospective assessment, not what the 1941 documents state. The National Archives article of August 3, 2026 states that when the letter became known within Bletchley Park it generated institutional friction and that the four signatories were informally referred to as the “wicked uncles”, a characterization that does not appear in any 1941 document cited in the file.
What HW 1/155 settles: a staffing crisis was documented in precise terms, it reached the Prime Minister within a day of dispatch, and Churchill directed it be resolved as the highest available priority. What the file does not settle: when every specific request was honored, whether the July 1941 WRNS commitment was ultimately fulfilled and by what date, and what formal consequences, if any, the four men faced within GC&CS. The record ends on November 18, 1941, and those questions remain open in it.